Treating compound and method



United States Patent 2,987,527 TREATING COMPOUND AND METHOD Donald E. Sincroft, Fort Wayne, and Endre F. Sipos, Decatur, Ind., assignors to Central Soya Company, Inc., Fort Wayne, Ind a corporation of Indiana No Drawing. Filed Feb. 16, 1959, Ser. No. 793,268 17 Claims. (Cl. 260-403) This invention relates to a treating compound and method. The compound or composition is particularly useful in the treating of gasoline for the control and reduction of intake system deposits, carburetor cleaning,

rust and Corrosion control, anti-icing, bacteriostatic action, and other results. The composition is also useful as a releasing, softening and wetting agent in textile manufacture and as a dispersing agent for pigment concentrates in paints and other vehicles.

This application is a continuation-in-part of our copending application, Serial No. 695,540, filed November 12, 1957.

The invention is particularly useful as a gasoline additive. Although numerous gasoline additive products with detergency action are available on the market, their use for keeping intake or induction systems and carburetor clean is limited in many respects. Most of the synthetic detergents are very expensive or are not compatible with gasoline and with the additives of gasoline, or their detergency action is so strong that the settling out of metallic ions after the treatment of the gasoline by the producer is prevented or delayed, and an emulsion is formed between the gasoline and the water bottoms in storage tanks, with a subsequent loss of valuable additives to the water. Furthermore, the individual needs of each gasoline producer are so varied that no single ingredient or compound is suitable 'for adaptation to different optimal conditions.

An object of this invention is to provide a new composition or treating compound having unique surfacemodifying characteristics as compared with the starting materials. A further object of this invention is to provide an economical, effective compound for eliminating the build-up of carburetor and intake manifold deposits during normal vehicle operation when used with gasolines of widely varying composition. A still further object is to provide a composition for treating gasoline which is not only compatible with gasolines of widely varying composition but also with gasolines having the common gasoline additives and with substantially no adverse efiect on O.R.I. (octane rating increase) or disturbance to the composition and to the physical characteristics of the gasoline for the beneficial actions of eliminating carburetor and intake manifold deposits, anti-icing, rust control, and other benefits which will be hereinafter set forth. Yet another object is to provide a method for the treatment of gasolines of widely varying composition and having therein the common gasoline additives now employed for an effective detergency and prevention of the build-up of carburetor and intake manifold deposits without contributing to the problems that are encountered in the storage of gasoline. Other specific objects and advantages will appear as the specification proceeds.

In one embodiment of the invention, commercial filtered lecithin containing a low level of benzene-insoluble materials is diluted with petroleum oil such as, for example, 60 neutral oil, a staturated aliphatic hydrocarbon having 'an approximate molecular weight of 150. The extending agent, 60 neutral oil, improves the viscosity of lecithin and facilitates a uniform contact among the reacting materials. To the diluted lecithin body is then added an organic base which reacts with the acidic groups of the phosphatides and also neutralizes the residual free fatty acids always present in commercial lecithin preparations.

Patented June 6, 1961 In the practice of our invention, lecithin is brought into contact with N-aliphatic or alicyclic substituted polymethylene-diamines with the structural formula of in which the alkyl groups are derived from fatty acids. We prefer to employ an N-alkyl substituted propylene diamine. As a result of the foregoing, there is formed a reaction mixture which may be effectively employed with gasolines of widely varying composition and containing the common gasoline additives so as to bring about an effective detergency action without contributing to emulsion problems in the storage tanks and providing bacteriostatic action in the water bottoms. Moreover, the reaction mixture is found to have an anti-icing effect. The reaction mixture is characterized by 12l5% loss of titratable amines as soon as the lecithin comes into contact with the diamine compound. When the reactive mixture is allowed to stand for 16 hours at 150 F., there is an approximate loss of 35% titratable amines. After this sudden decrease of 35% titratable amines in the reaction mixture, an equilibrium occurs in storage, with the result that the final product has approximately 40% less titrattable amines than the amount originally present in the reacting ingredients. Infrared anaylsis showed a loss in primary and secondary amines after the reaction, with a consequent increase in amide linkages. This reaction probably represents several types of amide formation such as ammonolysis of glyceride linkages, dehydration of amine salts of fatty acids, and interaction between the phosphatidic groups of lecithin and the diamine. There is no loss of total nitrogen contact of the reactive mixture during the reaction phase.

The viscosity of lecithin is reduced from 50,000 centipoises to 2500 centipoises at F. This reduction is more than that which would be caused by a mere dilution effect.

There are, probably numerous other physico-chemical changes in addition to the foregoing, when one considers the complex nature of commercial soybean lecithin, but it is believed not necessary from the point of view of performance to go into such detailed characterization.

In the combining of the lecithin and diamine, as above described, there is formed a reaction mixture which reaches substantial equilibrium and which is characterized by a compound containing an amide linkage as determined by infrared spectroscopy and by the simultaneous loss of titratable amines. At 8.85 microns, the peaks representing the molecular vibration of the diamine compound are completely absent in the reaction mixture, while at the same time the characteristic amide peaks which were absent in the diamine and lecithin now appear.

The lecithin (to be reacted) is preferably a filtered lecithin, because the unfiltered lecithin product has a high benzene-insoluble residue from impurities (meal, dust, carbohydrates, etc.). Such impurities would lend a hazy appearance to lecithin in solvents, and they would also increase the deposit formation in the engine. The lecithin product is obtained by centrifugal separation from crude soybean oil, etc., dried to a moisture value of less than .8%, and filtered to a low benzene-insoluble value.

The dilution oil may be any petroleum oil that substantially lowers the viscosity of the lecithin and reduces the acetone-insoluble value of the lecithin material to approximately 50-65%.

The N-aliphatic or alicyclic substituted polymethylenediamines, which will be referred to hereinafter as fatty acid diamines, are strong organic bases having strong cationic activity. The alkyl group is derived usually from a fatty acid" or from a group of fatty acids such as those obtained by the hydrolysis of coconut oil, soybean oil, tallow, and other animal and vegetable oils. The ,diamines preferably contain both primary and secondary aminegroupings. Other aliphaticor' aromatic amines and quaternary compounds may also be used, if they are compatible with the gasoline mixture or if their usage is justified by some specified demand that they might fulfill more advantageously than the above-mentioned .fatty acid diamines. We prefer, however, the fatty acid diamines, because of their effective cationic activity which is operative without disturbing the composition of the gas'olines and the function of their solvents while also avoiding the formation of emulsions, etc.

The N-alkylated diamines can be any of the materials of the formula in which R can be hydrogen and R and R can be methyl groups as in the case of 3-dimethyl amino pro beneficial results, however, are obtained when the fatty acid diamine is used in the range of 1% to 50%. As a: specific example, the fatty acid diamine may be combined by weight with the lecithin in the proportion of of diamine to 80% of lecithin.

While, from the standpoint of Id'etergencyand other uses described herein, we have found the proportions of l-50% of the fatty acid diamine with 99-50% ofthe lecithin eflicacious, our preferredrange is 20-50% ofrthe fatty acid diamine compound and 80-50% of lecithin.- And where the reaction mixture is employed specifically for de-icing and other special uses, the proportions may be further varied in the range of 90-20% of the fatty pylamine. Similarly, R can be hydrogen and R and R can be ethyl groups or other alkyl groups containing l-4carbon atoms, as in the case of 3-diethyl amino propylamine or 3-isopropylaminopropylamine. Each amino group can contain an alkyl substituent such as in N,N- dimethylethylene-diamine or N,N-diisopropylethylenediamine, or N,N'dimethyl-l,3-propylenediamine, or N,N- diisopropyl-l,3-propylenediamine, or similar compounds.

While the specific operation of the organic base-lecithin reacted mixture for carrying out the above results is not completely understood, it is believed that the complex is preferentially adsorbed from the solvent onto metal surfaces even in the presence of Water, and that the complex plates out on a metal surface as closely packed monomolecular films and forms a highly effective diffusion barrier. This barrier film apparently serves as a chemical insulator by preventing further deposition of particles having afiinity to metal surfaces, thereby acting as an anti-icer, carburetor and intake manifold cleanser, and inhibiting corrosion, spark plug fouling conditions, and controlling surface ignition. The presence of phosphorus works synergistically with other phosphorus addi tives in converting the lead deposits to the lead orthophosphate form. In the lead orthophosphate form, the deposits have a higher glow point, and, therefore, provide a less critical condition that would promote the surface ignition firings.

The de-icing or anti-icing control is believed to be due to the hydrophobic mono-molecular film which tends to insulate the metal parts from the very sensitive and very volatile gasoline components. 7

It should also be pointed out that lecithin, in addition to being an anti-oxidant in its own right, has the ability to act synergistically with other materials which show anti-oxygenic activity. For example, it has been shown that lecithin can reenforce tremendously the action of phenolic anti-oxidants. This anti-oxidant property of lecithin is not lost in the lecithin-diamine reaction mixture and can be listed as an important marginal benefit of the invention. This is of particular interest because many of the accepted inhibitors or anti-oxidants that are being offered to the petroleum field today are phenolictype materials. It will also aid in maintaining the lubricating oil in clean condition despite the build-up of combustion products as normally occurs. Finally, because of lower viscosity of the lecithin-diamine reaction mixture, the handling characteristics, storage, transfer, and feeding thereof, are much better than that of ordinary lecithin. 7

The fatty acid diamine which is to be reacted with the lecithin may be varied in percentage within a substantial range. We prefere to combine by. weight from 10% to 40% of diamine with the lecithin for best results. Some acid diamine and 10-80% of lecithin, as set forth in greater detail in the copending application of Richard J. De Gray, filed on even date herewith as serial No. 793,- 252, and entitled Anti-stalling Additives and Motor Fuel Containing the Same.

From the foregoing and for all uses, the fatty acid diamine and lecithin are combined by weight in the range of -1% diamine and 10-99% lecithin. As already stated, best results have been obtained when the materials are combined in the proportions of 20-50% of the fatty acid diamine and 80-50% of lecithin.

The proportions of the lecithin-fatty acid-diamine reactive mixture blended with the gasoline may be in the range of 25-500 parts per million, the preferred range being 50-100 parts per million.

In the operation of the process, by way of example, the fatty acid diamine may be reacted with the lecithin at a temperature and for a period of time to reach substantial equilibrium. Equilibrium is usually reached when there has been a loss of about 30-40% of the titratable amines. We prefer to employ temperatures of about -150 F. for a period of at least 15 minutes, but, if desired, temperatures as low as 32 F. and up to 400 F. may be employed. In the foregoing, a reaction mixture is obtained which is characterized by the formation of amides which constitute at least 10% of the amines derived from the N-aliphatic or alicyclic substituted polymethylene-diamine.

By proportioning the amount of fatty acid diamine and lecithin, it is found that a selected surface-modifying action can be obtained to meet specific critical requirements and which is significantly different from the activity of the reacting ingredients.

The resultin reacted mixture gives an optimal surface action so that it is an effective releasing agent in textile manufacture while having an increased softening and wetting effect and, when employed in gasoline, has a marked cleansing effect on the carburetor and the intake system of gasoline engines. It has also excellent anti-icing properties.

. Specific examples of the compound and mode of treatment may be set out as follows:

Example I A commercial motor gasoline additive was prepared by blending in a filtered soybean lecithin and coconut fatty acid diamines at the levels of 55 parts per million.

had the following general formula:

H H H R-N-G-tii-t'i-N-H a a it 1'1 a where "R" represents alkyl groups derived from fatty Diarnine- Lecithin Product Lecithin Toluene Moisture-. Free Fatty Acids" Viscosity at 80 F Acetone Insolubl Phosphorus Nitrogen -.do

centipoisem- .percent..

'1 lecithin base diluted with 60-neutrsl 011.

After l6hours of contact at 130 F., there was a 35% loss in titratable amines while infrared analysis showed a loss in primary and'secondary amine content, with -a subsequent increase inamide linkages. As will be noted from the foregoing, the chemical structure, the acidity and viscosity of the lecithin was considerably reduced by the adding of the neutral oil and the coconut diamine. The resulting compound has substantially an ideal polarity for the gasolinemixture, i.e., it is an excellent cleanser for the intake system and carburetor while at the same time the ingredients cooperate in entirely eliminating emulsion problems. The combination of the diamine with the lecithin produces an excellent anti-icing property in addition to the detergency function, rust inhibition, the control of surface ignition, plug fouling, bacteriostatic action in water bottoms, etc.

Example II The process was carried on as described in Example 1 except that only lbs. of coconut fatty acid diamine and 90 lbs. of lecithin (diluted with 60 neutral oil) were .used per 100 lbs. total. The product gave excellent detergency with substantially no tendency for emulsion formation.

Example 111 The process was carried on as described in Example 1, except that to the lecithin were added'20 lbs. of soya 'fatty acid diamines having a combining molecular weight of 356 and a primary amine content of 40%. The product gave excellent anti-icing results while inhibiting corrosion, and the compound is recommended where changing surfaces of metal .from hydrophilic to hydrophobic properties is desired.

Example IV The process was carried on as described in Example III except that 20 lbs. of the monoand dioleate salts of tallow fatty acid diamines were added to the diluted lecithin. The product was 'found to have strong detergent properties, basteriostatic properties, and corrosioninhibiting properties.v

Example V The effect of the lecithin-diamine reaction mixture in maintaining carburetors-in a-clean condition and in cleaning carburetors which have become dirty, can be seen from this and the following example:

A total of 40 trucks operating in the city delivering newspapers were tested; 20 were Ford trucks and 20 were Dodge trucks. Each car was driven for approximately 8,000 miles over a period of approximately 4 months. Ten of the Ford trucks and 10 of the Dodge trucks had clean carburetors at the start of the test, and 10 of the Ford trucks and 10 of the Dodge trucks had normally dirty carburetors at the start of the test. Half of each of the above categories of trucks was operated on a regular gasoline base fuel composed of catalytic -'di'stillate,'catalytic reformate, catalytic polymer, and :straight run naphtha having an octane number'of approximately 90. Half of each of the categories of trucks was operated on the same fuel but containing 0.005% of the additive made in accordance with Example I. The cleanliness of the carburetors was rated by visual inspcction on an arbitrary scale comparable to the L4 varnish range scale, a rating 10 being assigned to a clean carburetor and a rating 0 being assigned to an extremely dirty carburetor fouled to the point of practical From this it will be seen that in trucks starting the test with clean carburetors, they became markedly dirtier when the base fuel did not contain the additive. In the trucks which started the test with dirty carburetors, the carburetors became dirtier on the fuel without the additive, but became appreciably cleaner when operated on the fuel with the additive.

Example VI In this example, three cars were employed to determine the effect of the additive in both city stop-and-go type driving and in sustained high speed driving, "such as encountered on turnpikes. Each car went through three phases, as follows:

Phase I was designed to build up deposits in a car starting with a clean carburetor. In this phase, the car was driven 400 miles on the same base fuel as in Example V, utilizing the following cycle: One mile at 25 miles per-hour, 5 minutes with a car idling ina .closed garage (breathing its own exhaust), 10 minutes with the engine turned oif, sitting in the garage in the presence of the exhaust fumes (which permitted the deposits to solidify). This cycle was repeated 400 times on a round-the-clock basis.

In phase H, the car with the deposits built up as above described was driven 400 miles, typical of stopand-go city driving, stabilizing the deposits. In this test, the car was driven through dense city traffic, with many stop lights, never exceeding 35 miles per hour.

In phase III, the car was driven 4,000 miles on a turnpike at 65 miles per hour, with full acceleration after a stop at each service plaza. The carburetors were rated at the beginning, at the end of phase I, at the end of phase II, and after each 1,000 miles in phase III, utilizing the same rating scale as in Example V.

In the following table, the Ford car was driven throughout on the base fuel; the Pontiac car was driven on the base fuel in phase I, and on base fuel plus 0.005% of the additive of the previous example in phases II and III; and the Plymouth car was driven on the base fuel in phase I and on the base fuel plus 0.01% of the additive in phases II and III. The results are as follows:

Ford Pontiac Plymouth In compounding the treating material with gasoline,

we have obtained efliective results by using the compound in the range of 25 to 500 parts per million. Best .results were obtained when the compound'was blended -lines of widely-varying composition --with substantially no disturbance to the physical characteristics of the gasoline.

While, in the foregoing specification, we have set forth specific steps and ingredients and proportions thereof in considerable detail, it will be understood that such details of procedure, proportions, etc., may be varied Widely by those skilled in the art without departing from the spirit of our invention. 7 7

We claim:

1. A surface-modifying composition, comprising a reaction mixture resulting from the reaction of 10-99 parts by weight of lecithin with 90-1 parts of N-alkyl substituted polymethylene-diamine, with the structural formula of RI I-(CH2)x--NHz in which the alkyl groups are derived from fatty acids, reacted at a temperature and for a time to reach substantial equilibrium, characterized by the formation of amides which constitute at least 10% of the amines derived from said polymethylene-diamine, and by the corresponding decrease in titratable amines.

2. The composition of claim 1 in which the lecithin is 50-80 parts of the polymethylene-diamine is 50-20 parts.

3. The composition of claim 1, in which the lecithin is about 80 parts and the polymethylene-diamine is about 20 parts.

4. The composition of claim 1, in which the lecithin is 1-50 parts and the polymethylene-diamine is 99-50 parts.

5. The composition of claim 1, in which the lecithin is diluted with an aliphatic hydrocarbon to an acetoneinsoluble value of about 50-65%.

6. A surface-modifying composition adapted to be added to gasoline, comprising the reaction mixture of 10-80 parts by weight of lecithin with 90-20 parts of an N-alkyl substituted propylene diamine in which the alkyl groups are derived from fatty acids having a chain length of C to C reacted at a temperature and for a time to reach an equilibrium, characterized by the formation of amides which constitute at least 10% of the amines derived from said propylene diamine and by the corresponding decrease in titratable amines.

7. A surface-modifying composition, comprising a reaction mixture resulting from the reaction of 50-99 parts by weight of lecithin with 1-50 parts of an N-alkyl substituted propylene diamine, in which the alkyl groups are derived from fatty acids having a chain length of C to C reacted at a temperature and for a time to reach an equilibrium, characterized by the formation of amides :which constitut t l ast" of e. m n= ;1fi rom; sai propy e e: d am n a d: b t sa i q s i s decrease in titratable amines. 7? *1 f 8. The composition of claim 7, i' which the alkyl groups of the propylenediamine are derived from the fatty acids obtained by the hydrolysis of coconut oil.

9. A surface-modifying composition, comprising a reacted mixture of soy lecithin with an N-alkylsubstituted polymethylene-diamine. e

10. In a method for preparing a surface-modifying composition, the steps of reacting lecithin with an N-alkyl substituted polymethylene-diamine having thestructural formula f v in which the alkyl groups are derived from fatty acids at a temperature and for a time to reach an equilibrium at-which-20-4-0% of the titratable amines are lost. 'l1.-The process of claim 10, inwhich thereacting 1 temperature is from 32 to 400 F. V 12. The process of claim 10, in which the temperatures 7 are maintained at from 100 to F. and for a period of not less than fifteen minutes. '13, The process of claim 10, in which the proportion of the polymethylene-diamine is from 1-50% by weight. w 14. The process of claim 10, in which the proportion of the polymethylene-diamine is from 10-40% byweight.

15. The process of claim 10, in which the proportion of polymethylene-diamine is about 20% by weight. j 16. In a process for. the preparation of a surface-moditying; composition, the steps of reacting about 80 parts by weight of lecithin with 20 parts by weight. of an N- alkyl substituted polymethylene-diamine with the structural formula of H R -iI-(GHzk-NH, in which the alkyl groups are derived from fatty acids, at a temperature between 32 and 400 F. until equilibrium is obtained, as determined by a reduction in the amine content of from 20-40%.

17. A treating compound for gasoline, comprising a reaction mixture resulting from the reaction of 50-99 parts by weight of lecithin with 1-50 parts of an N-alkyl substituted polymethylene-diamine having the formula of in which the alkyl groups are derived from fatty acids, characterized by the formation of amides which constitute at least 10% of the amines derived from said polymethylene-diamine, as determined by infrared spectroscopy.

References Cited in the file of this patent UNITED STATES PATENTS 2,208,105 Rathbun July 16, 1940 2,295,179 Loane Sept. 8,1942 2,352,760 Bell July 4, 1944 2,839,545 Hennessy et al June 17, 1958 2,885,414 Beal May 5, 1959 

1. A SURFACE-MODIFYING COMPOSITION, COMPRISING A REACTION MIXTURE RESULTING FROM THE REACTION OF 10-99 PARTS BY WEIGHT OF LECITHIN WITH 90-1 PARTS OF N-ALKYL SUBSTITUTED POLYMETHYLENE-DIAMINE, WITH THE STRUCTURAL FORMULA OF
 10. IN A METHOD FOR PREPARING A SURFACE-MODIFYING COMPOSITION, THE STEPS OF REACTING LECITHIN WITH AN N-ALKYL SUBSTITUTED POLYMETHYLENE-DIAMINE HAVING THE STRUCTURAL FORMULA 